New Zealand Journal of Marine and Freshwater Research abstracts
Validated ages, growth, and productivity parameters for silver warehou
(Seriolella punctata) off the south and east coasts of
South Island, New Zealand
PETER L. HORN
National Institute of Water & Atmospheric
Research Ltd
P. O. Box 14-901, Kilbirnie
Wellington, New Zealand
COLIN P. SUTTON
New Zealand Fishing Industry Board
Private Bag 24-901
Wellington
Abstract A method is described to determine the age of silver
warehou using the zones in sectioned otoliths. The technique was validated by
examining the state of otolith margins from fish sampled regularly over
1 year, and by following the progression of length modes in
length-frequency distributions (for age classes 0+ to 3+). Von Bertalanffy
growth parameters are estimated for silver warehou off the south-east coast of
South Island, New Zealand. The fish grow rapidly up to the time of first
spawning, but the annual growth increment decreases markedly after sexual
maturity (about 4-6 years). Growth in length is negligible after about 10
years. Female fish have a significantly faster rate of growth than males. An
estimate of 0.25 for instantaneous natural mortality (M) is proposed,
but instantaneous total mortality (Z) could not be estimated.
Keywords silver warehou; Seriolella punctata; age
validation; growth; productivity
New Zealand Journal of Marine and Freshwater Research, 1996, Vol 30:
301-312
0228-8330/96/3003-0301 $2.50/0 (c) The Royal Society of New Zealand
1996
PDF file of entire paper: medium quality (759K); (scanned from paper original: notes about this process)
This year's abstracts |
Journal home page |
All abstracts |
Publishing home page
